Just a few days before their court appearance, Mininova, the largest BitTorrent site on the Internet, has started to filter content. The site is using a third party content recognition system that will detect and remove torrent files that link to copyright infringing files.

Starting today, Mininova will use a content recognition system that detects and removes torrent files linking to copyright infringing files. The system will also prevent the torrents from being re-uploaded to mininova later on.

Mininova co-founder Niek told TorrentFreak that the system will be tested for 12 weeks with only a few titles. With this trial Mininova collaborates with an association representing several TV/movie content owners. Niek couldn’t tell us which one, but our best guess would be that it’s the MPA(A).

The content removal system should be seen as an extension of the existing copyright policy according to Niek, who also said that the current trial will be used to find out whether the content recognition system is a workable and effective solution.

The system was selected by the copyright holders themselves who want an easier way to get torrent files removed than the current notice and takedown policy, and it is operated by an undisclosed third party. Interestingly, this collaboration does not mean that the upcoming court case against BREIN is off the table.

Later this month BREIN hopes to convince the court that Mininova has to filter its search results, so that all .torrent files which may point to unauthorized content are removed. Up until now, Mininova refused to interfere with the search results, claiming that the DMCA take-down procedure they have is good enough. This has clearly changed now.

The response from Mininova’s users is mostly negative, with one commenter saying “Shame to see such a nice site decide to go hang itself,” and another adding “Wow, guess you guys are caving under the pressure. Too bad its all over now.”

The effectiveness of this filtering system, and how it will affect mininova’s popularity is yet to be seen, but it sure is a radical development.